<?
/**
 * filename: ext_page.class.php
 * @package:phpbean
 * @author :feifengxlq<feifengxlq#gmail.com><[url=http://www.phpobject.net/]http://www.phpobject.net/[/url]>
 * @copyright :Copyright 2006 feifengxlq
 * @license:version 2.0
 * @create:2006-5-31
 * @modify:2006-6-1
 * @modify:feifengxlq 2006-11-4
 * description:超强分页类，四种分页模式，默认采用类似baidu,google的分页风格。
 * 2.0增加功能：支持自定义风格，自定义样式，同时支持PHP4和PHP5,
 * to see detail,please visit [url=http://www.phpobject.net/blog/read.php]http://www.phpobject.net/blog/read.php[/url]?
 * example:
 * 模式四种分页模式：
   require_once('../libs/classes/page.class.php');
   $page=new page(array('total'=>1000,'perpage'=>20));
   echo 'mode:1<br>'.$page->show();
   echo '<hr>mode:2<br>'.$page->show(2);
   echo '<hr>mode:3<br>'.$page->show(3);
   echo '<hr>mode:4<br>'.$page->show(4);
   开启AJAX：
   $ajaxpage=new page(array('total'=>1000,'perpage'=>20,'ajax'=>'ajax_page','page_name'=>'test'));
   echo 'mode:1<br>'.$ajaxpage->show();
   采用继承自定义分页显示模式：
   demo:http://www.phpobject.net/blog
 */
class page
{
 /**
  * config ,public
  */
 var $page_name="per_page";//page标签，用来控制url页。比如说xxx.php?PB_page=2中的PB_page
 var $next_page='>';//下一页
 var $pre_page='<';//上一页
 var $first_page='First';//首页
 var $last_page='Last';//尾页
 var $pre_bar='<<';//上一分页条
 var $next_bar='>>';//下一分页条
 var $format_left='[';
 var $format_right=']';
 var $is_ajax=false;//是否支持AJAX分页模式
 var $ajax=false;//判断select参数
 var $divid="";//判断div参数

 /**
  * private
  *
  */
 var $pagebarnum=10;//控制记录条的个数。
 var $totalpage=0;//总页数
 var $ajax_action_name='';//AJAX动作名
 var $nowindex=1;//当前页
 var $url="";//url地址头
 var $offset=0;

 /**
  * constructor构造函数
  *
  * @param array $array['total'],$array['perpage'],$array['nowindex'],$array['url'],$array['ajax']...
  */
function page($array,$ajax=false,$divid="")
{
	$this->ajax = $ajax;
	$this->divid = $divid;
	if(is_array($array)){
		if(!array_key_exists('total',$array))$this->error(__FUNCTION__,'need a param of total');
		$total=intval($array['total']);
		$perpage=(array_key_exists('perpage',$array))?intval($array['perpage']):10;
		$nowindex=(array_key_exists('nowindex',$array))?intval($array['nowindex']):'';
		$url=(array_key_exists('url',$array))?$array['url']:'';
	}else{
		$total=$array;
		$perpage=10;
		$nowindex='';
		$url='';
	}
	if((!is_int($total))||($total<0))$this->error(__FUNCTION__,$total.' is not a positive integer!');
	if((!is_int($perpage))||($perpage<=0))$this->error(__FUNCTION__,$perpage.' is not a positive integer!');
	if(!empty($array['page_name']))$this->set('page_name',$array['page_name']);//设置pagename
	$this->total=$total;
	$this->perpage=$perpage;
	$this->_set_nowindex($nowindex);//设置当前页
	$this->url=$url;
	$this->_set_url($url);//设置链接地址
	$this->totalpage=ceil($total/$perpage);
	$this->offset=($this->nowindex-1)*$this->perpage;
	if(!empty($array['ajax']))$this->open_ajax($array['ajax']);//打开AJAX模式
}
/**
* 设定类中指定变量名的值，如果改变量不属于这个类，将throw一个exception
*
* @param string $var
* @param string $value
*/
function set($var,$value)
{
	if ( in_array($var,get_object_vars($this)) ){
		$this->$var=$value;
	}
	else {
		$this->error(__FUNCTION__,$var." does not belong to PB_Page!");
	}
}
/**
* 打开倒AJAX模式
*
* @param string $action 默认ajax触发的动作。
*/
function open_ajax($action)
{
	$this->is_ajax=true;
	$this->ajax_action_name=$action;
}
/**
* 获取显示"下一页"的代码
*
* @param string $style
* @return string
*/
function next_page($style='')
{
	if($this->nowindex<$this->totalpage){
	return $this->_get_link($this->_get_url($this->nowindex+1),$this->next_page,$style);
}
	return '<span class="'.$style.'">'.$this->next_page.'</span>';
}

/**
* 获取显示“上一页”的代码
*
* @param string $style
* @return string
*/
function pre_page($style='')
{
	if($this->nowindex>1){
		return $this->_get_link($this->_get_url($this->nowindex-1),$this->pre_page,$style);
	}
	return '<span class="'.$style.'">'.$this->pre_page.'</span>';
}

/**
* 获取显示“首页”的代码
*
* @return string
*/
function first_page($style='')
{
	if( $this->nowindex==1 ) {
		return '<span class="'.$style.'">'.$this->first_page.'</span>';
	}
	return $this->_get_link($this->_get_url(1),$this->first_page,$style);
}

/**
* 获取显示“尾页”的代码
*
* @return string
*/
function last_page($style='')
{
	if($this->nowindex==$this->totalpage){
		return '<span class="'.$style.'">'.$this->last_page.'</span>';
	}
	return $this->_get_link($this->_get_url($this->totalpage),$this->last_page,$style);
}

function nowbar($style='',$nowindex_style='')
{
	$plus=ceil($this->pagebarnum/2);
	if($this->pagebarnum-$plus+$this->nowindex>$this->totalpage)$plus=($this->pagebarnum-$this->totalpage+$this->nowindex);
	$begin=$this->nowindex-$plus+1;
	$begin=($begin>=1)?$begin:1;
	$return='';
	for($i=$begin;$i<$begin+$this->pagebarnum;$i++){
		if($i<=$this->totalpage){
			if($i!=$this->nowindex)
			$return.=$this->_get_text($this->_get_link($this->_get_url($i),$i,$style));
			else
			$return.=$this->_get_text('<span class="'.$nowindex_style.'">'.$i.'</span>');
		}
		else{
			break;
		}
		$return.=" ";
	}
	unset($begin);
	return $return;
}
/**
* 获取显示跳转按钮的代码
*
* @return string
*/
function select()
{
	if($this->ajax && isset($this->divid)){
		$return="<select name='PB_Page_Select'  onchange='selectload(\"$this->divid\",\"$this->url\"+this.value);'>";
	}else{
		$return="<select name='PB_Page_Select'  onchange='window.location=\"$this->url\"+this.value'>";
	}
	for($i=1;$i<=$this->totalpage;$i++){
		if($i==$this->nowindex){
			$return.='<option value="'.$i.'" selected>'.$i.'</option>';
		}else{
			$return.='<option value="'.$i.'">'.$i.'</option>';
		}
	}
	unset($i);
	$return.='</select>';
	return $return;
}

/**
* 获取mysql 语句中limit需要的值
*
* @return string
*/
function offset()
{
	return $this->offset;
}

/**
* 控制分页显示风格（你可以增加相应的风格）
*
* @param int $mode
* @return string
*/
function show($mode=1)
{
	//$startPage="显示第 <B>".($this->total?($this->offset()+1):0)."</B>-<B>".min($this->offset()+$this->perpage,$this->total)."</B> 条记录，共".$this->total."条记录";
	//$endPage="&nbsp;&nbsp;共<b>".$this->totalpage."</b>页";
	$startPage = '';
	$endPage = '';
	switch ($mode)
	{
		case '1':
		$this->next_page='下一页';
		$this->pre_page='上一页';
		return $startPage.$this->pre_page().$this->nowbar().$this->next_page().'第'.$this->select().'页'.$endPage.' 总计'.$this->total.'行';
		break;
		case '2':
		$this->next_page=' 下一页 ';
		$this->pre_page=' 上一页 ';
		$this->first_page=' 首页 ';
		$this->last_page=' 尾页 ';
		return  $startPage.$this->first_page().$this->pre_page().'[第'.$this->nowindex.'页]'.$this->next_page().$this->last_page().'第'.$this->select().'页'.$endPage;
		break;
		case '3':
		$this->next_page='下一页';
		$this->pre_page='上一页';
		$this->first_page='首页';
		$this->last_page='尾页';
		return $startPage.$this->first_page().$this->pre_page().$this->next_page().$this->last_page().$endPage;
		break;
		case '4':
		//$this->next_page='下一页';
		$this->next_page='<img src="images/nextpage.gif" border="0"/>';
		//$this->pre_page='上一页';
		$this->pre_page='<img src="images/prevpage.gif" border="0"/>';
		return $startPage.$this->pre_page().$this->nowbar('red2','page').$this->next_page().$endPage;
		break;
		case '5':
		return $this->pre_bar().$this->pre_page().$this->nowbar().$this->next_page().$this->next_bar();
		break;
	}
}
/*----------------private function (私有方法)-----------------------------------------------------------*/
/**
* 设置url头地址
* @param: String $url
* @return boolean
*/
function _set_url($url="")
{
	if(!empty($url)){
		//手动设置
		$this->url=$url.((stristr($url,'?'))?'&':'?').$this->page_name."=";
	}
	else{
		//自动获取
		if(empty($_SERVER['QUERY_STRING'])){
			//不存在QUERY_STRING时
			$this->url=$_SERVER['REQUEST_URI']."?".$this->page_name."=";
		}
		else{
			//
			if(stristr($_SERVER['QUERY_STRING'],$this->page_name.'=')){
				//地址存在页面参数
				$this->url=str_replace($this->page_name.'='.$this->nowindex,'',$_SERVER['REQUEST_URI']);
				$last=$this->url[strlen($this->url)-1];
					if($last=='?'||$last=='&'){
						$this->url.=$this->page_name."=";
					}else{
						$this->url.='&'.$this->page_name."=";
					}
			}
			else{
				$this->url=$_SERVER['REQUEST_URI'].'&'.$this->page_name.'=';
			}//end if
			}//end if
	}//end if
}

/**
* 设置当前页面
*
*/
function _set_nowindex($nowindex)
{
	if(empty($nowindex)){
		//系统获取
		if(isset($_GET[$this->page_name])){
			$this->nowindex=intval($_GET[$this->page_name]);
		}
		}else{
		//手动设置
			$this->nowindex=intval($nowindex);
	}
}

/**
* 为指定的页面返回地址值
*
* @param int $pageno
* @return string $url
*/
function _get_url($pageno=1)
{
	return $this->url.$pageno;
}

/**
* 获取分页显示文字，比如说默认情况下_get_text('<a href="">1</a>')将返回[<a href="">1</a>]
*
* @param String $str
* @return string $url
*/
function _get_text($str)
{
	return $this->format_left.$str.$this->format_right;
}

/**
* 获取链接地址
*/
function _get_link($url,$text,$style=''){
	$style=(empty($style))?'':'class="'.$style.'"';
	if($this->is_ajax){
		//如果是使用AJAX模式
		return '<a '.$style.' href="javascript:'.$this->ajax_action_name.'('.$url.')">'.$text.'</a>';
	}else{
		return '<a '.$style.' href="'.$url.'">'.$text.'</a>';
	}
}
/**
* 出错处理方式
*/
function error($function,$errormsg)
{
	die('Error in file <b>'.__FILE__.'</b> ,Function <b>'.$function.'()</b> :'.$errormsg);
}
}
?>
